CVE-2022-39173
CVE-2022-39173 is a high-severity vulnerability in Wolfssl with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- EPSS exploit prediction: 4% (90th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-787
- Affected product: Wolfssl
- Published:
- Last modified:
Description
In wolfSSL before 5.5.1, malicious clients can cause a buffer overflow during a TLS 1.3 handshake. This occurs when an attacker supposedly resumes a previous TLS session. During the resumption Client Hello a Hello Retry Request must be triggered. Both Client Hellos are required to contain a list of duplicate cipher suites to trigger the buffer overflow. In total, two Client Hellos have to be sent: one in the resumed session, and a second one as a response to a Hello Retry Request message.
Frequently asked questions
- What is CVE-2022-39173?
- In wolfSSL before 5.5.1, malicious clients can cause a buffer overflow during a TLS 1.3 handshake. This occurs when an attacker supposedly resumes a previous TLS session. During the resumption Client Hello a Hello Retry Request must be triggered. Both Client Hellos are required to contain a list of duplicate cipher suites to trigger the buffer overflow. In total, two Client Hellos have to be sent: one in the resumed session, and a second one as a response to a Hello Retry Request message.
- How severe is CVE-2022-39173?
- CVE-2022-39173 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2022-39173 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2022-39173?
- CVE-2022-39173 affects Wolfssl. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2022-39173?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2022-39173 published?
- CVE-2022-39173 was published on 2022-09-29 and last updated on 2026-06-17.
References
- http://packetstormsecurity.com/files/169600/wolfSSL-Buffer-Overflow.html
- http://seclists.org/fulldisclosure/2022/Oct/24
- https://blog.trailofbits.com/2023/01/12/wolfssl-vulnerabilities-tlspuffin-fuzzing-ssh/
- https://github.com/wolfSSL/wolfssl/releases
- https://www.wolfssl.com/docs/security-vulnerabilities/
Affected products (1)
- cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*
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